JPH1144281A - Stop device of internal combustion engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide the stop device of an internal combustion engine to reliably stop the ignition device of the internal combustion engine only by a single operation of a switch without increasing a product cost. SOLUTION: A first transistor 16 is connected between the two ends of the primary coil 2 of an ignition coil 4 consisting of primary and secondary coils 2 and 3. A second transistor 17 is connected between the two ends of the primary coil 2 and connected to the base (an input part) of the first transistor 16. A stop switch 8 is operated only while an operation force is exerted. A capacitor 13 is connected in series to a stop switch 8, and the generating current (an output) of the ignition coil 4 is charged. A resistor 14 is connected in series to the capacitor 13 and the stop switch 8 and connected to the base (an input part) of the second transistor 17 to form the discharge route of the capacitor 13.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a stop device for an internal combustion engine, and more particularly to a stop device for an internal combustion engine that can reliably stop the internal combustion engine only by operating the engine stop switch with one touch. .

[0002]

2. Description of the Related Art A conventional ignition device for an internal combustion engine has a circuit configuration as shown in FIG. FIG. 2 shows an ignition device of a magnet ignition type internal combustion engine used for a small motorcycle engine, a general-purpose engine, a generator engine and the like.

In FIG. 2, an ignition device 1 includes an ignition (power generation) coil 4 having a primary coil 2 and a secondary coil 3,
An ignition plug 5 connected to the secondary coil 3 and an intermittent switch 6 connected between both ends of the primary coil and intermittently turning on / off a mechanical contact by a cam or the like;
A noise absorbing capacitor 7 that absorbs noise generated by turning on / off the power supply, and a push-button stop switch 8 that is connected to both ends of the primary coil 2 and that operates only while an operating force is applied. It is configured. A rotary magnet 10 rotated by an engine 9 is magnetically coupled to the ignition coil 4. When the engine 9 rotates, an AC voltage is generated in the primary coil 2, and the AC voltage is intermittently switched by an intermittent switch 6. Then, a voltage boosted by the secondary coil 3 is generated by the intermittent operation, and the boosted voltage is discharged by the spark plug 5.

When the engine 9 is stopped, a stop switch (stop device) 8 is operated to ground the primary coil 2 so as not to generate a high voltage in the secondary coil 3, thereby stopping the engine.

[0005]

SUMMARY OF THE INVENTION The above-described ignition device 1
Is a configuration in which, when the engine 9 is stopped, the stop switch 8 is turned on (contacts are closed) and the secondary coil is grounded to stop the ignition operation.
Is rotated by inertial force for about 2 to 3 seconds,
If the stop switch 8 is turned off (contacts are opened) within the above time, the engine 9 is restarted. The above problem can be solved by holding the operating force, for example, by continuing to ground the secondary coil using a lever-type switch or the like, but when the engine 9 is started next time, the switch must be released. It can be mistaken for a fault and is not a complete solution. Also, since a power generation signal of about several hundred volts is intermittently applied to the primary coil 2, when the stop switch 8 is connected between both ends of the primary coil 2, an expensive stop switch 8 that can withstand the voltage is used. Therefore, there is a problem that the product cost as an apparatus is increased.

Accordingly, the present invention focuses on the above-mentioned problems, and a stop device for an internal combustion engine which can reliably stop an ignition device of the internal combustion engine without increasing the product cost and only by one-touch operation of a switch. Is provided.

[0007]

According to the present invention, a first transistor connected between both ends of an ignition coil and a first transistor connected between both ends of the ignition coil are provided. A second transistor connected to the input of the transistor, a switch that operates only while an operating force is applied, a capacitor connected in series with the switch, and charging the output of the ignition coil; Connected to the switch and the second
And a resistor forming a discharge path of the capacitor.

Further, a Zener diode or a resistor is connected in parallel with the capacitor.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An internal combustion engine stop device according to the present invention comprises:
A first transistor 16 connected between both ends of the primary coil 2 of the ignition coil 4 composed of the primary coil 2 and the secondary coil 3, and a first transistor 16 connected between both ends of the primary coil 2 A second transistor 17 connected to the base (input unit) of the ignition coil 4, a stop switch 8 that operates only while the operating force is applied, and a series connection to the stop switch )
And a resistor 14 connected to the capacitor 13 and the stop switch 8 and connected to the base (input unit) of the second transistor 17 to form a discharge path for the capacitor 13. Things. With such a configuration, the ignition operation of the internal combustion engine can be reliably stopped by only one-touch operation of the stop switch 8, so that the secondary coil is grounded using a conventional lever-type switch or the like that holds the operating force. The stop device stops the ignition operation of the internal combustion engine. In the past, expensive stop switches that could withstand high voltages had to be provided.
According to the present invention, since a low-pressure stop switch can be used, the manufacturing cost of the device can be reduced.

A Zener diode 23 or a resistor is connected in parallel with the capacitor 13,
Since the capacitor 13 can be prevented from being excessively charged, a good charge / discharge circuit of the holding means 15 composed of the capacitor 13 and the resistor 14 can be obtained.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an internal combustion engine stopping device according to the present invention will be described with reference to the embodiments shown in the accompanying drawings.

FIG. 1 is a circuit diagram showing a stop device for an internal combustion engine according to an embodiment of the present invention. In FIG. 1, reference numeral 4 denotes an ignition coil, and one ends of a primary coil 2 and a secondary coil 3 are connected to the ground and an ignition plug 5. Reference numeral 8 denotes a stop switch including a push button switch that operates only while an operation force is being applied, and is connected to the multi-end side of the primary coil 2. 9 is an engine and 10 is a rotating magnet. 1
Reference numeral 1 denotes a stopping device which is a feature of the present invention.

The stop device 11 includes a switching circuit 12 for controlling the intermittent operation of the ignition coil 4, a capacitor 13 for storing the electric charge generated from the ignition coil 4, and a capacitor 13.
Holding means 1 for stopping the operation of switching circuit 12 for a predetermined time
And 5.

The switching circuit 12 has a first transistor 16 and a second transistor 17 each composed of an NPN transistor. The collector and the emitter of the first transistor 16 are connected between both ends of the primary coil 2 of the ignition coil 4, the collector of the first transistor 16 is connected to the stop switch 8, and the base of the first transistor 16 is connected to the stop switch 8. The second transistor 17 via the resistor 18
Connected to the collector. Second transistor 17
Is connected to a resistor 19, and this resistor 1
The emitters of the ninth and second transistors are connected across the primary coil. Further, the second transistor 17
Is connected between both ends of the primary coil 2 via the respective bias resistors 20 and 21.

The holding means 15 has one end of the capacitor 13 connected to the stop switch 8 via a diode 22 (the anode of the diode 22 is connected to the stop switch 8).
The cathode side of the diode 22 is connected to the capacitor 13), and the capacitor 13 is connected to the resistor 14 in series. This resistor 14 is connected to the base of the second transistor 17 and forms a discharge path for the electric charge accumulated in the capacitor 13. Further, a Zener diode 23 is connected in parallel to the capacitor 13, and the Zener diode 23 adjusts the charging current of the capacitor 13.

Next, the operation of the stop device of the present invention will be described.

First, the stop switch 8 is turned off (open).
The operation of the stop device for the internal combustion engine when the operation is performed will be described. The rotating magnet 10, which is magnetically coupled, rotates according to the rotation of the engine 9, and an intermittent power generation voltage is generated in the primary coil 2 with the rotation of the rotating magnet 10. The generated voltage is applied to the collector and the base of the first transistor 16, so that the first transistor 16 operates and the generated current flows to the ground as the collector current of the first transistor 16. The generated current after the operation of the first transistor 16 is equal to the bias resistance 2
The second transistor 17 set to operate near the maximum value of the generated current by 0, 21 flows from the collector current of the first transistor 16 to the ground as the collector current of the second transistor 17 (second Is turned on, the first transistor is turned off). By repeating the above-described operation in accordance with the generation of the intermittent power generation voltage, a high voltage is generated on the secondary coil 3 side of the ignition coil 4, and the ignition is continued by discharging by the ignition plug 5.

Next, the stop switch 8 is turned on (short).
The operation of the stop device for the internal combustion engine in the case where the operation is performed will be described. When the stop switch 8 is turned on with one touch, the generated current is charged from the stop switch 8 via the diode 22 to the capacitor 13 by the voltage of the Zener diode. The charging current charged in the capacitor 13 is equal to the resistance 14
, And flows into the base of the second transistor 17 as a discharge current, so that the second transistor 17 is forcibly operated by the discharge current. Therefore, the first transistor 16 is forcibly turned off by a time constant determined by the capacitor 13 and the resistor 14, so that even if a generated current is generated by the inertial force of the engine 9, the first transistor 16 will The ignition action stops.
The setting of the time constant of the holding means constituted by the capacitor 13 and the resistor 14 is performed by setting the time from the stop of the ignition operation to the complete stop of the rotation of the engine 9 due to the inertial force (usually 2 to 3 times). Seconds).

The stop device 11 for an internal combustion engine having such a configuration is
The ignition operation of the internal combustion engine can be reliably stopped only by one-touch operation of the stop switch 8. Therefore, the internal combustion engine stop device of the present invention is compared with a conventional stop device that continues to ground the secondary coil by using a lever-type switch or the like that holds an operating force and stops the ignition operation of the internal combustion engine. There is no risk of being mistaken for a failure. Conventionally, an expensive stop switch that can withstand a high voltage had to be provided, but by adopting the above-described circuit configuration, a low-voltage stop switch can be used. Can be suppressed.

Further, since the Zener diode is connected in parallel with the capacitor 13 of the holding means 15, it is possible to prevent the capacitor 13 from being excessively charged. Therefore, a good charge / discharge circuit of the holding means 15 can be obtained. is there.

Further, the present invention may be used for a function of automatically stopping the engine 9 when the oil level of the engine oil becomes equal to or lower than a predetermined value by using the above-described circuit. This can be easily achieved by connecting a reed switch 24 to the circuit instead of the stop switch 8. A float having a magnet is arranged floating in the oil, and when there is sufficient oil, the reed switch 24 is turned off. However, when the oil becomes less than a predetermined amount, the float magnet lowers to the height of the reed switch 24. By turning on the reed switch 24, the ignition action of the internal combustion engine is stopped.

Accordingly, by applying the reed switch 24 for judging the oil level to the circuit of the present invention, even if chattering of the reed switch 24 occurs due to fluctuations in the oil level, the ignition operation of the internal combustion engine can be stopped reliably. Therefore, it is possible to provide a highly reliable system as a stop device for an internal combustion engine.

In this embodiment, the Zener diode 23 is connected in parallel with the capacitor 13 to adjust the charge amount of the capacitor 13 of the holding circuit 15, but the charging current is adjusted by a resistor instead of the Zener diode 23. You may do it.

[0024]

The present invention provides a first transistor connected between both ends of a fire coil, and a second transistor connected between both ends of the ignition coil and connected to an input of the first transistor. A transistor, a switch that operates only while an operating force is applied, a capacitor connected in series with the switch, and a capacitor for charging the output of the ignition coil; and a second capacitor connected to the capacitor and the switch. And a resistor connected to the input of the transistor and forming a discharge path of the capacitor. The ignition operation of the internal combustion engine can be reliably stopped only by one-touch operation of the switch. Conventionally, an expensive switch that can withstand a high voltage has to be provided. However, since a switch for a low voltage can be used, the manufacturing cost of the device can be reduced.

Further, since a zener diode or a resistor is connected in parallel with the capacitor, excessive charging of the capacitor can be avoided, and thus a holding device composed of the capacitor and the resistor is used. A good charging / discharging circuit can be obtained.

[Brief description of the drawings]

FIG. 1 is a circuit diagram of a stop device for an internal combustion engine showing an embodiment of the present invention.

FIG. 2 is a circuit diagram showing a conventional ignition device for an internal combustion engine.

[Explanation of symbols]

 2 Primary coil 3 Secondary coil 4 Ignition coil 5 Spark plug 8 Stop switch 9 Engine 10 Rotary magnet 11 Stop device 12 Switching circuit 13 Capacitor 14 Resistance 15 Holding means 16 First transistor 17 Second transistor 23 Zener diode

Continued on the front page (72) Inventor Hisataka Kobayashi 1-1190-1, Fujibashi, Nagaoka City, Niigata Prefecture Japan Seiki Co., Ltd. R & D Center (72) Inventor Ryuichi Ando 1-1190 Fujihashi, Nagaoka City, Niigata Prefecture Japan Seiki Co., Ltd. Company R & D Center

Claims (2)

[Claims] A first transistor connected across the ignition coil; a second transistor connected across the ignition coil and connected to an input of the first transistor; A switch that operates only while force is being applied, and a switch that is connected in series with the switch,
A capacitor that charges the output of the ignition coil, and a resistor that is connected to the capacitor and the switch and that is connected to an input of the second transistor and forms a discharge path of the capacitor. A stopping device for an internal combustion engine. 2. The internal combustion engine stopping device according to claim 1, wherein a zener diode or a resistor is connected in parallel with the capacitor.